Well bit cutter mounting



- March 22, 1938. A. c. CATLAND WELL BIT CUTTER MOUNTING Filed Sept. 25; 1936 2 Sheets-Sheet 1 .1 r \\\\\\\TT March 22, 19,38. A. c:.- ATLAND I WELL BIT CUTTER MOUNTING Filed Sept. 25, 1936 '2 Sheets- Sheet 2 are 72b) g proved anti-friction bearings for roller cutters companying drawings, in which:

it formed of hard material wear very rapidly, par Fig. i. Fig. i is an enlarged fragmentary detailed well bit that embodies a series of balls arranged lowing detailed disclosure I will describe several between the interioriof'the' cutter and the'cutter typicalforms of theinvention rotatably mountcarrying bushing in a manner to assume both the ing the cutters of a well bit of the character fully radial thrusts and the end thrusts imposed on described and claimed in my co pendi'ng applithe cutter. cation entitled Roller rock bit", Serial No. 88,989, 30

' bushing for transmitting the principal end opposite wings l2. The major portions of the tented Mar. 212,

WELL BET @UTTER MOUN'EHNG Alfred C. Catland, Alhambra, Calii., assignorto Globe Oil Tools Company, Los Nietos, iDalih, a corporation oi Caliilornia I 1 Application September 25, 1936, Serial No. 102,527

r oi. (oi. 255-71) a This invention relates to well drilling tools and tion will be fully understood from the following relates more particularly to the mountings or detailed description of typical preferred forms bearings for the roller cutters of well bits. A and applications of my invention; throughout generalobject of this invention is to provide imwhich description reference is made to the acthat are efiicient and long wearing. I Fig. 1 is a side elevation of a well bit embody- Roller rock bits have been employed embodying the bearings provided by the present inven ing rollers for rotatably supporting the roller tion illustrating the lower portion of the bit in cutters on the pins or shafts of the bits. Such central vertical cross section. Fig. 2 is an en- 10 hearings or rollers are only capable'of assuming larged fragmentary'detailed sectional view taken it the radial loads or thrusts and it has been the as indicated by line 22 on Fig. 1. Fig. 3 is a accepted practice to provide thrust washers at fragmentary vertical detailed sectional view of the ends of the cutters to assume the end thrusts. the lower portion of the bit taken in a plane Thrust washers even though they be hard or at right angles to the plane of the sectioning in ticularly where abrasive earth. formations are sectional view of the bearing for supporting one encountered in the wells. of the outer cutters. Fig. 5 is an enlarged frag- --Another object of this invention is to provide inentary longitudinal sectionalview of the hearan improved anti-friction bearing for the roller ing means for supporting one of the inner cutters so cutter of a well bit that embodies a series of and Fig. 6 is a view similar to Fig. 4'illustrating anti-friction members that take or assume both a slightly modified form of bearing.

the radial and axial thrusts or loads "thereby The cutter mounting means or bearings proeliminating thenecessity for thrust washers. vided by the present invention are adapted to Another object of this invention is toprovide be p yed r a y Supporting the roller amounting or bearing for the roller cutter of a, cutters of various forms of well bits. In the fol- Another object of this invention is to provide file'd July 6, 1936. a cutter bearing of the character mentioned that The bit illustrated in the drawin cludes provides a series of balls within each end pora shankorbody it adapted to be connected with tion of the cutter to transmit the radial thrusts a rotar'y welldrilling string, The body II] has a 3 5 as well as the end thrusts in both directions. tapered threaded socket H in its upper end for Another object of this invention is to provide r v n a p on the drill collar Orother p rt an improved cutter supporting bearing of the of'the drilling string. Two diametrically oppocharacterr'nentioned in which the points of consite legs 01 Wi 1 P j downwardly and tactv of the balls with the interior of the cutter slightly outwardly r t e lower d f he 40 and the bearingbushing lie in a plane substanbody ill. The wings l2 have flat Substantially 40 tially normal to '61 at right angles to the prinvertical inner surfaces l3. Flat substantially cipal formation engaging edges of the cutter t horizontal shoulders it occur on the wings l2 sheet the most efiicient operation of the bearing. at he lower ends f their in r' ur 'a t. The Another object of this invention is to provide y "W f her includes two Opposite l s or an improved bearing means for rotatably sup- Wings e W s l5 pl'o w dly and 45 portingthe cutter of a bit that is simple and in-' u d y from the lower end of e y W expensive and that is easy to assemble. and are space substantially 90 from the wings A further object of this'invention is to provide ewin s it ve fia dow wardly and outan anti-friction bearing for the roller cutter of d y in inner Surfaces and fl S oula.- well bit that embodisrollers for assuming or ders ll on their lower ends. 5o transmitting the radial thrusts and a series of A cutter carrying shaft or pin l8 extends across ,balls acting between the cutter and a bearing the open lower end of the body l0 between the thrusts and a portion of the radial thrusts. pin l8 are inclined upwardly and inwardly to- The. various objects and features of my lnv nward the central vertical axis of the bit. The 55 of the pin l8 to connect the intermediate portion it of the pin 48 is cylindrical and substantially horizontal. Screws it are passed through openings in the wings i2 and threaded into openings in the opposite ends pin and the, wings I 2. The heads of the screws i9 may have portions i9 peened into notches in the outer sides of the wings l2 to prevent unthreading of the screws. The cutter supporting pin it has reduced end portions 20 adjacent the inner sides of the wings I2. A central web 2! projects from the lower end of the body It! and has two downwardly and outwardly projecting wings 22 spaced inwardly from the wings H5. The outer sides 23 of the wings 22 are flat and parallel with the surfaces I6 of the wings l5. Flat shoulders 22 occur on the lower ends of the wings 22. Cutter supporting pins 24 are passed outwardly through openings in the wings 22 and are threade'd in openings 25 in the wings H5. The outer end portions of the pins 24 have parts distorted or peened into notches 28 in the outer sides of the wings l5. The heads of the screws 24 may have similar parts distorted into notches 2? in the inner sides of the wings 22. The parts of the screws 24 peened into the notches 28 and 217 positively prevent unthreading of the cutter supporting pins 24 when the tool is in operation. In the event that one peened over portion of a pin 24 may be worn away through contact with the earth formation the other may remain to prevent loss of the pin.

A stud 28 is arranged through a vertical opening 29 in the body web 2i. The lower portion of the stud 28 is enlarged and has an opening 38 receiving the intermediate portion l8 of the pin I8 whereby the stud serves to support the pin between its ends. A connecting pin 3i may be arranged through transverse openings in the stud 28 and the portion l8 of the pin i8. A nut 32 is threaded on the projecting upper end of the stud 28 to retain the stud in position. Fluid discharge members 33 are arranged in spaced openings in the body ID to discharge the circulation fluid downwardly against the cutters on the. pin. The nut 32 may serve to hold the discharge members 33 in position.

The bit further includes two like outer cutters A supported on the pins 24 through the bearings provided by the invention and a set of inner cutters B and C rotatably supported on each inclined portion of the frusto-conical having peripheral cutting teeth 34 provided with inclined or pitched cutting edges 35. The opposite ends of the cutters A may be flat and normal to the axis of the cutters. The ends and the interiors of the cutters A are formed to cooperate with the bearing means of the invention as will be hereinafter described.

The inner cutters B are cylindrical roller cutters provided with peripheral cutting teeth 36. The opposite ends of the cutters B may be flat and the inner ends of the cutters may be recessed or relieved to receive adjacent parts of the web 2i. The cutters B may be rotatably supported on the pin l8 by series of anti-friction rollers 3?. Suitable washers 88 may space the inner ends of the rollers 21 from the adjacent faces of the web 2|. The inner cutters C which surround the pin it between the cutters B and the wings. l2 are frusto-conical cutters, provided with peripheral teeth 39 having pitched or inclined cutting edges 40. The cutters C are arranged with their large ends facing outwardly. The inner ends of the cutters C may be flat and normal to the axes of pin N. The outer cutters A are the cutters. The interiors of the cutters C and their outer ends are shaped or formed to cooperate with the bearing means provided by the invention as will be hereinafter described.

The bearing means provided by the present invention and illustrated in Figs. 1, 2 and 4 of the drawings for rotatably supporting each outer cutter A includes, generally, annular surfaces or races 4i and 42 on the interior of the cutter, a sectional bushing 43 on the cutter supporting pin 24 and series of balls 44 cooperating with the races 4! and 42 and the bushing 43.

The surfaces or races 4| and 42 are provided on the interior of the cutter A to partially receive and to cooperate with the balls 44. The races 4! and 42 are alike in shape and may be of the same diameter. In accordance with the invention the races ll and 42 are spherically concaved to have proper cooperation with the balls 44. The races 4| and 42 are oppositely disposed, that is, the race 4i faces toward the adjacent wing I5, while the race 42 faces toward the adjacent wing 22. The races 4! and 42 on the interior of the cutter A are spaced axially by an annular ridge 45 on the interior of the cutter A. The cutter A may have cylindrical internal surfaces 46 extending inwardly from its ends to merge with the races 4i and 42. The surfaces or races 4! and 42 may 'extend or curve inwardly to the internal or peripheral surface of the ridge 45. Annular sockets or recesses 41 are provided in the opposite ends of the cutter A. The above described ridge 45 is substantially equally spaced between the opposite ends of the cutter A so that the races 4| and 42 are substantially equally spaced from the central transverse plane of the cutter.

The bearing bushing 43 is provided on the pin 24 to be engaged by the series of balls 44. The bushing 43 is preferably sectional to facilitate the assembly of the balls 44 within the cutter A. In practice the bushing 43 includes two similar or like sections 48. The sections 48 are tubular and surround the pin 24. The pushing sections 48 are complementary and oppositely disposed to have their inner ends in abutment as illustrated. An annular flange 49 is provided on the outer end of each bushing section 48. The outer side of the flange 49 of the outermost section 48 cooperates with the inner surface I6 of the adjacent wing l5 while the outer surface of the flange 49 on the other bushing section 48 cooperates with the surface 23 of the adjacent wing 22. The peripheral portions of the flanges 49 are received or partially received in the recesses 41 as illustrated. The flange 49 of the outer section 48 has a projecting tongue 58 cooperating with the shoulder H to prevent rotation of that section. The flange 49 of the inner section 48 has a similar tongue 5| cooperating with the shoulder 22 to prevent rotation of that section. The flanges 49 fitting the recesses 41 close the outer ends of the ball carrying space within the cutter A. Each bushing section 48 is provided with a spherically concaved surface or race 52. The race 52 of the outer bushing section 48 opposes the race 4| while the race 52 of the inner section 48 opposes the race 42. The races 52 occur in the corners between the peripheries of the bushing sections 48 and the inner sides 53 of the flanges 49. The peripheries of the sections 48 and the inner surfaces 53 of the flanges 49 preferably merge with the races 52, as illustrated. The pemay be normal to the longitudinal axes of the sections 48; i

The series .of balls 44 are arranged within the cutter A to cooperate with the sets or pairs of opposing races 4| and 52 and 42 and 52. The balls 44 are operable. to transmit the radial thrusts is an important feature of the invention that the sets of races 4| and 52 and 42 and 52 are related so that the balls 44 assume the axial thrusts in both directions; as well as the full radial thrusts. This action results from'the location and relation of the faces 4| and 42 on the interior of the I cutter A and the location of the races 52 in the corner between the peripheries of the sections 48 I and the inner surfaces 53 of the flanges 5| .p While the disposition of the races 4| and 42 and 52 may be varied somewhat and yet attain the desired result it is preferred to provide and locate the races so that a line extending through the central points of contact of a ball 44 with the race 4| and the race 52 is substantially normal to thecutting edge35 of a tooth 34 as illustrated in Fig. 4 of the drawings. This particular relationship has been found to be most practical and to provide for the full transinissionof the principal axial thrust of the cutter ,A as well as the radial thrusts with a minimum of friction and wear.

: Due to the inclination of the cutter A the heavier or principal end thrusts are imposed on the balls .44 cooperating with the races 4| and 52. The balls 44 cooperating with the races 42 and '52 of course assume the other end thrusts.

Fig. 6 ofthe drawings illustrates a slightly modified form'ofbearing for rotatably supporting an inclined roller cutter A. The cutter A may be substantially the same as one of the above described cutters A and is provided with two internal races 4| and 42 The races 4| and 42 may be substantially the same as the above described races 4| and 42. The bearing means for rotatably supporting the cutter A includes two bushing sections 48" and 48'" similar, gener ally to-the above described bushing sections 48. The bushing sections 48 and 48 surround andare supported by a pin 24 which may be identical with one of the pins 24. The bushing secti0ns48 and 48 are arranged in opposing end to end relation with their inner ends inlcooperati'on. Flanges 48" corresponding to the flanges 49 are provided on the outer ends of the sections '48 and 48 The section 48"- is provided with a ball race 52 and the section 48 is provided with a ball race 52. In the structure illustrated in' Fig. 6 of the drawings the bushing section 48 is somewhat larger in effective diameter than the section 48" so that it's race 52 is larger in diameter than the race 52". Annular rows or series of balls 44'- are arranged within the cutter A to cooperate with the opposing races of the cutter and the bushing sections 48 and 48 The balls 44' of the two rows or series may be of the same diameter and where the race 52 is larger in effective diameter than the race 52 the'race 4| of the cutter is preferably larger in efiective diameter than the race 42 to properly accommodate the balls 44". The balls 44 cooperate with the sets of races 4| and 52* and 75. 42 and 52 in the same manner as the races cutter mounting.

longitudinal axis of the pin l8.

and balls in the above described form of the Owing to the inclination or pitch of the cutter A the principal or heavy end thrusts are imposed on the balls 44 cooperating with the races 4| and 52 Owing to the fact that the races 4| and 52 are larger in eifective diameter than the races 42 and 52 they present'larger bearing surfaces and a larger number of balls 44 may cooperate with them for the dependable transmission of the heavy end thrusts.

hearing or mounting means,, it being understood that such description is also applicable to the means for supporting theother cutter C.

The major inner portion of the cutter C is cylindrical and its wall is concentric with the An annular or tubular series of rollers 68 surrounds the pin l8 within the inner portion of the cutter C to have .rolling cooperation with the pin l8 and the cylindrical interior of the cutter. A suitable thrust washer 63 is interposed between the inner ends of the rollers 68 and the adjacent ends of the rollers 31 and the cutter B. It will be apparent how the bearing rollers 68 assume most of the radial thrusts to which the cutter C is subjected.

An annular recess 64occurs in the outer end of the cutter C. The-recess 64 is deepened or extends into the cutter C to have a spherically concaved ball race 65. The race 65 occurs in what may be termed the corner between a radial wall and an axial wall of tlierec'ess 64. The race 65 is spherically concaved-to properly cooperate with the series of balls 62'.

The bushing 6| is arranged on the reduced end portion 28 of the pin 8 and has an internal shoulder 66 cooperating with the shoulder 61 of the pin l8 which occurs at the inner end of its reduced-portion 20. The bushing 6| extends inwardly to have its inner portion surrounding the body of the pin l8 within the cutter C. The inner end of the bushing 6| is adjacent or cooperates with the outer ends of the rollers 60 and thus limits outward movement of the rollers. The bushing 6| is provided with an annular flange "68 whose outer surface cooperates with the "surface l3 of the adjacent wing l2. A tongue 69 is provided on the flange 68 to cooperate with the shoulder M of the adjacent wing |2 to prevent rotation of the bushing 6|. .The flange 68 is partially received in the ecess 64 of the cutter C and serves to close the outer end of the ball receiving space within the cutter. An annular spherically concaved ball race 'lllis provided on the bushing 6|. The race '18 opposes the race 65 of the cutter C. The race 18 occurs in the corner between the inner surface of the flange 68 and the periphery of the bushing 6|.

I The annular series of balls 62 is arranged in the cutter C to cooperate with the opposing races 65 which the-cutter C is subjected and assume some of theradia l thrusts on the cutter. It is to be noted that a line extending through the points of contact of a ball 62 with the races 85 and i is substantially perpendicular to the longitudinal axis of the cutter C and the edges of the cutter teeth.

It is believed that the operation ofthe cutter supporting bearings of the present invention will be readily understood from the foregoing detailed description. The bearings rotatably supporting the outer cutters A involve the two rows of balls 44 which assume all of the end thrusts as well as the radial thrusts and the bearing does not involve thrust washers that are subjected to rapid wear. The cutter bearings are dependable and the balls 44 and 62 cannot become lost or displaced. The bushing sections or bushing parts are dependably locked against loss and displacement and cannot rotate. The bearings are simple and embody a minimum number of parts. The bearings for the outer cutters involve the sectional bushings 43 facilitating the assembling of the cutters and bearing parts. The series of balls cooperating with the interiors of the cutters support the cutters for free rotation with a minimum of friction and wear.

Having described only typical preferred forms and applications of my invention. I do not wish to be limited or restricted to the specific details herein set forth, but wish to reserve to myself any variations or modifications that may appear to those skilled in the art or fall within the scope of the following claims:

l Having described my invention I claim:

'1. In a well bit, a supporting pin, a rotatable cutter, an internal ridge in the cutter spaced between its ends, ball races on the opposite sides of the ridge, a sectional bushing on the pin having end flanges overhanging the ends of the cutter, ball races in the bushing opposing the first named races, and series of balls cooperating with the sets of opposing races to rotatably support the cutter.

2. In a well bit, a supporting pin, a rotatable cutter, an internal ridge in the cutter spaced between its ends, ball races on the opposite sides of the ridge, a bushing on the pin, flanges on the bushing engaging the opposite ends of the cutter, ball races in the bushing occurring in the corners between the flanges and the peripheries of the bushings to oppose the races on the ridge, and series of balls cooperating with the sets of opposing racesto rotatably support the cutter.

3.- In a well bit, a supporting pin, a rotatable 1 with the sets of opposing races to rotatably sup- POrt the cutter.

4. In a well drilling bit, a supporting pin, a rotatable cutter, rollers rotatably supporting the cutter on the pin, a bushing on the pin entering one end of the cutter and overlapping said end of the cutter to close it, opposing races in the cutter and bushing and balls cooperating with the races, the races being related so that a line passing through the points of contact of a ball with races is pitched relative to the axis of rotation of the cutter whereby the balls assume the end thrusts on the cutter.

5. In a well bit, a supporting pin, a rotatable cutter, an internal ridge on the interior of the cutter spaced between its ends, a ball race on a side of the'ridge, a bushing on the pin having an end flange overlapping an end of the cutter, a ball race on the bushing opposing the first named race,

and a series of balls cooperating with the said races to rotatably support the cutter.

6. In a well bit, a straight cylindrical supporting pin, a rotatable cutter having internal ball races, a bushing comprising sections slid on the pin to extend into the ends of the cutter, flanges on the bushing sections projecting radially outward to overlap the ends of the cutter, each bushing section having a race opposing a race on the cutter, and balls cooperating with the opposing races to rotatably support the cutter.

7. In a well bit, a straight cylindrical supporting pin, a rotatable cutter having internalball races, a bushing comprising sections slid on the pin to extend into the ends of the cutter, flanges on the bushing sections projecting radially outward to overlap the ends of the cutter, parts on the cutter overlapping t1": peripheries of the flanges, each bushing section having a race opposing a race on the cutter, and balls cooperating with the opposing races to rotatably support the cutter.

ALFRED C. CA'I'LAND. 

